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2015-03-30

We all started off as babies, and I am sure that not many of you remember that one of the first toys you played with (and if you do not remember - then I am sure those of you with kids have probably done the same with your children) was a plastic container with different shapes on the lid and blocks that were made of different shapes.

A triangle would only go into the triangle, a circle in the circle, a block in the block and so on.

This is a basic skill that teaches us that no matter how hard we try, there are some things that just do not work. Things can only work in a certain way (of course coordination, patience and whole lot of other educational things).

It is a skill that we acquire, it takes time, patience, everyone gets there in the end.

And why am I blogging about this – you may ask?

This analogy came up a few days ago in a discussion of a way to provide a highly available database in the cloud.

And it got me thinking….

There are certain things that are not meant to be deployed in a cloud environment because they were never meant to be there in the first place. The application needed an Oracle database and it was supposed to be deployed in a cloud environment.

What is the default way to deploy Oracle in highly available configuration? Oracle RAC. There are a number of basic requirements (simplified) you need for Oracle RAC.

Shared disk between the nodes. That will not work in a cloud environment. So we can try using dNFS – as the shared storage for the nodes – that might work..But then you have to make an NFS mount available to the nodes – in the cloud.So let’s deploy an NFS node as part of the solution.But then we have to make that NFS node highly available.

Multicast between the nodes - that also does not work well in the cloud.So maybe create a networking environment in the cloud that will support multicast? Deploy a router appliance in the cloud.Now connect all the instances in the cloud into the router.But the router poses as a single point of failure.Make the router highly available.

And if not Oracle RAC – then how about Data Guard – which does not require shared storage?

But it has a steep licensing fee. And you have to find a way for managing the virtual IP address – that you not necessarily will have control over.But that can be overcome by deploying a VRRP solution with IP addresses that are manually managed.

ENOUGH!!!

Trying to fit a triangle into a square – yes if you push hard enough (it will break the lid and fit).If you cry hard enough – Mom/Dad will come over and put it in for you.

Or you come up with half-assbaked solution like the one below…

Some things will not fit. Trying to make them fit creates even more (and sometimes even bigger) problems.

In this case the solution should have been - change the code to use a NoSQL database that can be deployed easily and reliably in a cloud environment.

When trying to put in a vCenter as the target for deployment it will throw an error.

I actually find this really silly and a really weird move on behalf of VMware. Why limit this to connecting directly to an ESXi host?

Also I am quite intrigued to know what is the benefit of using such a tool for deployment. I do understand that VMware wanted to provide a generic tool that could be used on any platform to deploy a vCenter Server. If you look at the ISO that is provided for download – you will see a folder structure there for all platforms in the vcsa-cli-installer

But this got me thinking. The VCSA is appliance after all – which means it is probably an OVF – like most of VMware’s appliances.

Disclaimer – This is probably not supported – definitely not endorsed by VMware – so use it at your own risk!

I went and did some detective work. The ISO is about 3GB in size which means that it actually has to be appliance is probably there somewhere. It was not hard to find.

In the VCSA folder you will find a file vmware-vcsa which is almost 2GB in size.

It is obvious that the file is not an OVF – but probably an OVA – because of its size.

So for my test I copied the vmware-vcsa file and added the .OVA extension to the file

I then proceeded to deploy this appliance as I would any virtual appliance. I even went so far as to use the vSphere Client!

I was skeptical to see if there was actually anything extra that was put into the installer – because we all know that it most of the customization is provided within the OVF itself. I checked to see if the same functionality is available from both the new installer and a regular vSphere client deployment. The feature parity seems to be equal at least – with some addiitonal functionality that is available only when deploying as a virtual appliance.

Such as Inventory Location

Choice of Cluster / Host

And most importantly – the option to deploy to a Distributed vSwitch – something that is not possible when directly to a host. It would only recognize a Standard vSwitch

All the rest was mostly all the same.

Now of course there a things that are not visible in the regular installation interface – things that related to the upgrade.

So there you have it – Deploying a vCenter Server Appliance – directly into an existing vCenter.

Sometimes the stuff we are used to is the stuff that is also the easiest way to do things.

If anyone has any insight to problems that might occur using this method please feel free to leave them in the comments below, and of course – please feel free to leave any other thoughts or comments as well.

2015-03-14

This is the second half of my thoughts on the vSphere 6.0 release notes. Part 1 can be found here

Disclaimer: These are my own thought and ramblings. I think they should be questions you should be asking VMware, your TAM and the support people. These are not the only items in the Release Notes - just those that got my attention. Your mileage may differ and there may be other things that are of importance in the original document.

Takeaways:

Another NFS 4.1 caveat.

Makes me think that as with all new technologies – maybe we should wait until it is more stable and not jump into it feet first.

Takeaways:

Same As Above

It seems this is an all or nothing so no mixing between NFS versions – because this will cause problems.

Takeaways:

Same As Above

Takeaways:

This is not really an error – but by design. It seems that people will have learn how to interact with vVOLs – as opposed to the way they are used to working.

Questions:

Why is the default thick?

If there are certain Storage solutions that do not support thick – then why not make the default thin?

Questions:

If it might fail – why even give the option?

Will it always fail? Ad if not –is there a common denominator that causes the failure?

Takeaways:

Dell and QLogic specific. Learn the implications if this is relevant to your environment.

Takeaways:

It is always good to wait a while until the worms come out of the cracks.

Questions:

Does Emulex have a solution?

Questions:

If the features does not work – why enable it?

Is it possible to automate this? If so how?

Takeaways:

Another whopper. If you suffer an APD (which can happen) and you are using Flash Cache. the I/O acceleration will not work properly until the VM undergoes a power cycle to re-enable functionality.

Questions:

Is it possible to create some kind of report to find which machines can / have been affected?

If a full power off/on required – or is a restart of the VM sufficient?

Takeaways:

This is strange – because the storage policy is based on the disk itself and should have no dependency on the VM itself.

Questions:

What are the implications of having different storage policies for different machines?

When will this be fixed?

Is there a way to automate this?

Takeaways:

If you have a problem with your local RAID controller – this can cause your host to crash.

Questions:

Is this a bug?

With ESXi?

The MegaRaid driver?

When will this be fixed?

Questions:

Is it not possible to put in a check to or a delay to alleviate this problem?

Takeaways:

Again an all or nothing. Make sure that your plugins support 6.0 before the upgrade – otherwise you will not be able to use them.

Takeaways:

There will be certain cases that adding a new LUN will require a full reboot of the host.

Check to see if this is relevant to your environment

Questions:

If the LUN is added – not by the storage array tool – will this also happen?

Takeaways:

Seems to be another LSI issue.

Will not display in any event – and can only be obtained from the CLI.

Questions:

If the the information is there – why is it not displayed?

Takeaways:

Evidently a bug

Questions:

When will it be fixed?

Takeaways:

Wasn’t the purpose of having Host Profiles being able to take a current host and make a profile from it?

Questions:

Won’t changing the IP address of the Host (to a static one) cause a disconnect of the host?

Will this effect VM’s?

Can this be done live?

Questions:

Why done they restart?

Windows Only?

is service-control for both the Windows vCenter and the appliance?

Takeaways:

Good to know this information.

Takeaways:

If I remember correctly the service console was retired with ESXi 5.0 – Quite a while back? Was that not enough time to remove this?

Takeaways:

This is really a case of WYSIWYG (What you see is what you get)

Questions:

Can or will this be fixed?

Was this also an issue in previous versions?

Takeaways:

Using the Web client doesn’t always seem to work. It seems that it would be a good idea to use one or the other client but not mix and match.

Takeaways:

I guess permissions are not always what they seem – you might need a little something extra.

Takeaways:

Who was the genius who chose this name

Questions:

Is this being worked on with the Anti-virus vendors to solve this?

Who says that if I copy it back to the location – that the AV will not quarantine it again (whack-a-mole anyone)?